Processing facilities are often managed using process control systems. Example processing facilities include manufacturing plants, chemical plants, crude oil refineries, and ore processing plants. Among other operations, process control systems typically manage the use of motors, valves, and other industrial equipment in the processing facilities.
In conventional process control systems, controllers are often used to control the operation of the industrial equipment in the processing facilities. The controllers could, for example, monitor and control the operation of the industrial equipment and generate alarms when malfunctions occur.
“Control processes” are often implemented in conventional controllers using “function blocks.” Control processes typically represent processes or functions implemented by the conventional controllers to control the industrial equipment in the processing facilities. Function blocks typically represent executable software objects that perform specific tasks. Any of a wide range of functions could be represented by the function blocks. A combination of particular function blocks may be used to implement a specific control process in a conventional controller.
Graphical interfaces may represent the function blocks using symbols (such as rectangles) that have specified parameters (such as inputs and outputs). Control processes may be defined graphically by selecting appropriate function blocks and linking the selected function blocks. For example, a graphical interface could be used to select function blocks and link the inputs and outputs of the symbols representing the selected function blocks. This allows processing facility operators who purchase or use the conventional controllers to create and modify control processes for particular processing facilities. However, the facility operators often have no mechanism for creating or editing the types of function blocks available in the conventional controllers or for creating or editing the parameters associated with those function block types.